He noted on January 7, 1610 that Jupiter appeared to have three fixed stars nearby. Intrigued, he returned to the planet the following night, expecting the then-retrograde body to have moved from east to west, leaving the three little stars behind. Instead, Jupiter seemed to have moved to the east.
Puzzled by the planet's behavior, Galileo returned to the formation repeatedly, observing several key details.
First, the little stars never left Jupiter, but appeared to be carried along with the planet. Second, as they were carried along, they changed their position with respect to each other and to Jupiter. Finally, he discovered a fourth little star. These "stars" were in fact moons orbiting the planet: Io, Europa, Ganymede and Callisto This was the first empirical support for Copernicus' theory that the sun, and not the Earth, was at the center of the solar system. Galileo published this groundbreaking observation in his book Sidereus Nuncius (Starry Messenger), which appeared in Venice in March 1610, guaranteeing his fame and ensuring his place in scientific history
LEGO Galileo naturally has his trusty telescope by his side as he journeys into space. As for the other two figurines, Jupiter shares a name with the giant planet, while the spacecraft is named after Juno. But there's more to the underlying symbolism than that. Here's NASA's explanation:
In Greek and Roman mythology, Jupiter drew a veil of clouds around himself to hide his mischief. From Mount Olympus, Juno was able to peer through the clouds and reveal Jupiter's true nature. Juno holds a magnifying glass to signify her search for the truth, while her husband holds a lightning bolt
The Juno spacecraft will also carry a plaque in Galileo's honor, emblazoned with his likeness and his own handwritten notes concerning his observations of Jupiter's moons.
The launch for Juno is currently slated for Friday, August 5th, with a window that extends through August 26th.